Secure and efficient real-time communication with minimal latency is a critical requirement for public safety organizations and first responders. Toward that end, the Telecommunications Industry Association (TIA) adopted and standardized a suite of Land Mobile Radio (LMR) standards termed Project 25 (P25), as described for example, in the TIA 102-series documents. The P25 standard defines the operation and interfaces of P25-compliant radio systems. Additionally, through a gateway, non-compliant radio systems can also operate in a P25 network. The P25 standard also defines, in part, a standard for narrowband trunked systems.
As one example, portable radio transceivers or “walkie-talkies” are often implemented within a narrowband trunked network to quickly establish direct one-to-one and one-to-many communication links. Such radio transceivers are indispensable for law enforcement, rescue, and military personnel, and have even become commonplace across various business environments as well as for recreational activities. In particular, radio transceivers provide a near instantaneous connection between users in a talk group by utilizing push to talk (PTT) communications over a half-duplex radio transmission system, for example, over a circuit-switched network
Advances in cellular packet-switched networks have resulted in the development of a broadband push to talk over cellular (PoC) application, for example, as described in PoC V 1.0.3 Enabler Package released September 2009 by Open Mobile Alliance (OMA). Specifically, a PoC network provides a half-duplex voice over internet protocol (VoIP) solution, with well-known PTT functionality. PoC is implemented on an internet protocol multimedia subsystem (IMS) platform, as described in 3GPP Technical Specification (TS) 23.228 and any subsequent revisions. Moreover, PoC employs familiar protocols for voice and control signaling, including Real-Time Transport Protocol (RTP), as described, for example, in Request for Comments (RFC) 3550 dated July 2003 by Internet Engineering Task Force (IETF) and any subsequent revisions, and Session Initiation Protocol (SIP), for example, as described in RFC 3261 published June 2002 by IETF Network Working Group and any subsequent revisions.
In order to maintain the security of radio and/or other types of communication within a communication network, a reliable authentication scheme is needed. In SIP, hypertext transfer protocol (HTTP) digest authentication, as described, for example, in RFC 2617 dated June 1999 by IETF and any subsequent revisions, is used to authenticate a SIP client to a SIP server. For HTTP digest authentication to work, both the SIP client and the SIP server have to have a shared password which is manually configured in both the SIP client and SIP server. Furthermore, for multiple SIP clients, each SIP client also needs to be manually configured. In the event of a password change, the new password needs to be manually changed in both the SIP clients and the SIP server. Additionally, HTTP digest authentication requires the SIP client to resend appropriate authentication values to the SIP server for every message sent. Thus, a use may be prompted multiple times to provide a username, password, or other security credentials in order to access SIP services. Accordingly, there is a need for a system and method for providing an integrated and mutual authentication in a communication network.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various embodiments. In addition, the description and drawings do not necessarily require the order illustrated. It will be further appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required.
Apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the various embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Thus, it will be appreciated that for simplicity and clarity of illustration, common and well-understood elements that are useful or necessary in a commercially feasible embodiment may not be depicted in order to facilitate a less obstructed view of these various embodiments.